Position detection device

• US 9,343,647 B2
• Filed: 04/19/2012
• Issued: 05/17/2016
• Est. Priority Date: 05/09/2011
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kirihara, Akihiro, Endoh, Hiroyuki, Nakamura, Yasunobu
• Primary Examiner(s): Lin, James
• Assistant Examiner(s): McClain, William E
• Application Number:
  US14/114,508
• Publication Number:
  US 20140048115A1
• Time in Patent Office: 1,489 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/046 by electromagnetic means
• CPC Class Codes: H10N 10/17 characterised by the structure or configuration of the cell or thermocouple forming the device
• CPC Class Codes: H10N 19/00 Integrated devices, or assemblies of multiple devices, comprising at least one thermoelectric or thermomagnetic element covered by groups H10N10/00 - H10N15/00

Abstract

A position detection device includes a thermoelectric conversion portion which includes a magnetic layer and a plurality of electrodes. The magnetic layer has magnetization. The plurality of electrodes are formed of a material having spin-orbit interaction, and are formed on the magnetic layer so as to extend in a direction which intersects with the magnetization direction of the magnetic layer. When an arbitrary location on the layer-surface of the magnetic layer is heated, the thermoelectric conversion portion modulates the effective temperature in the magnetic layer and induces a spin Seebeck effect. As a result, the thermoelectric conversion portion generates, from the plurality of electrodes, a voltage corresponding to the heated position as position information.

Claims

1. A position detection device, comprising:

a thermoelectric conversion portion including;

a magnetic layer having magnetization; and

a plurality of electrodes which comprise a material having spin-orbit interaction and are formed on the magnetic layer so as to extend in a direction intersecting a magnetization direction of the magnetic layer,

wherein the thermoelectric conversion portion modulates an effective temperature in the magnetic layer so as to induce a spin Seebeck effect when an arbitrary location on a layer-surface of the magnetic layer is heated, and generates a voltage corresponding to a heated position from the plurality of electrodes as position information,

wherein the plurality of electrodes are disposed in a matrix, including a first electrode group and a second electrode group that are perpendicular to each other,

wherein the first electrode group and the second electrode group include electrodes disposed in parallel to one another, respectively,

wherein the electrodes of the first electrode group have an angle of 45 degrees to the magnetization direction of the magnetic layer, and

wherein the electrodes of the second electrode group have an angle of 45 degrees to the magnetization direction of the magnetic layer, and

wherein a thickness of the plurality of electrodes disposed in the matrix are equal to a spin diffusion length of the electrode material.

2. The position detection device according to claim 1, further comprising heating means provided separately from the thermoelectric conversion portion, for heating the arbitrary location on the layer-surface of the magnetic layer, the heating means being a heated object, heat from vibration, electromagnetic waves, chemical reactions, or phase changes.

3. The position detection device according to claim 1, further comprising an electromagnetic wave detection portion which is formed on the thermoelectric conversion portion correspondingly to the magnetic layer, and includes an electromagnetic wave absorption layer absorbing an electromagnetic wave so as to generate heat,

wherein the electromagnetic wave detection portion generates heat based on an electromagnetic wave applied to a location corresponding to the arbitrary location on the layer-surface of the magnetic layer, to thereby heat the arbitrary location on the layer-surface of the magnetic layer.

4. The position detection device according to claim 1, further comprising a friction detection portion which is formed on the thermoelectric conversion portion correspondingly to the magnetic layer, and includes a friction heat generating layer generating heat by friction,

wherein the friction detection portion generates heat based on a friction applied to a location corresponding to the arbitrary location on the layer-surface of the magnetic layer, to thereby heat the arbitrary location on the layer-surface of the magnetic layer.

5. The position detection device according to claim 1, further comprising a floating substance detection portion which is formed on the thermoelectric conversion portion correspondingly to the magnetic layer, and includes a floating substance detection layer generating heat by a chemical reaction when a specific floating substance is adhered,

wherein the floating substance detection portion generates heat based on the chemical reaction due to the floating substance adhered to an arbitrary surface position, to thereby heat the arbitrary location on the layer-surface of the magnetic layer.

6. The position detection device according to claim 1, wherein a stationary temperature gradient is applied to the magnetic layer.

7. The position detection device according to claim 1, wherein the thermoelectric conversion portion modulates a lattice temperature or a magnon temperature as the effective temperature in the magnetic layer.

8. The position detection device according to claim 1, wherein the plurality of electrodes are disposed at first and second ends of the magnetic layer.

9. The position detection device according to claim 1, further comprising an insulating layer for electric insulation between the plurality of electrodes.

10. The position detection device according to claim 1, further comprising a cover layer for protecting the position detection device.

11. The position detection device according to claim 1, further comprising:

a cover layer for protecting the position detection device; and

a wavelength filter disposed above the cover layer so as to detect a specific wavelength.

12. The position detection device according to claim 1, further comprising a floating substance detection portion that includes a floating substance detection film for adsorbing a floating substance, and is disposed on the magnetic layer via a spacer layer.

13. The position detection device according to claim 1, wherein the position detection device is unconnected to an external power supply.